Impact of Alpinia galanga rhizome extract on Bactrocera dorsalis population

The Bactrocera dorsalis (Hendel) is one of the most economically damaging pests and generally is controlled by insecticides. This research was done by evaluate the impact of rhizomes of Alpinia galanga extract on population of B. dorsalis. The rhizome of A. galanga was extracted by Soxhlet's apparatus using hexane, dichloromethane, ethyl acetate and 95% ethanol as separated solvent system. Various concentrations of all crude extracts were trailed by Topical spray application with adult B. dorsalis, completely randomized designs, 5 replicates. The results showed hexane crude extract gave the highest control efficiency to adult B. dorsalis which the 24 hours-LC50 values was 4,866.06 +/- 184.52 ppm (hexane), 24,156.66 +/- 880.33 ppm (dichloromethane), 16,744.73 +/- 641.27 ppm (ethyl acetate) and 6,337.54 +/- 145.42 ppm (95% ethanol). Thus, this extract may an alternative way for control this insect pest in the future.